Located some 100 kms south east of Sydney, Bargo is on the Hume Highway and the Sydney Melbourne rail line, together with a rail connection to the coal loader at Port Kembla.
On May 11th, 1970, an agreement between:-
A. & A. Brown & Abermain Seaham Collieries Limited, a fully owned subsidiary of Coal & Allied Industries Limited (Coal & Allied Operations Pty Ltd.)
The Newcastle Wallsend Coal Company Pty Ltd, a fully owned subsidiary of Peko-Wallsend Ltd.
was signed allowing exploration for coal over some 4000 hectares in the Bargo district.
Feasibility studies were undertaken in 1971 and upgraded in 1972.
During this period the mining industry suffered a severe downturn prompting a decision to defer the initial development work but continue with the Environmental Impact Statement studies.
In 1974, the Broken Hill Pty Co. Ltd joined the venture as an equal third participant through its wholly owned subsidiary, Dampier Mining Co. Ltd. and was signed off as the Bargo Joint Venture Agreement on July 21st, 1975.
Coal Lease 186 (Nov. 8th, 1978), Shire of Wollondilly and Shire of Mittagong, County of Camden and referred to as the “Bargo area”.
Exploration Licence No. 275 for 4040 ha was granted on 23rd March, 1970 in satisfaction of Exploration Licence Application No. 713, lodged on 18th Nov, 1969.
Nov 8th 1978 Coal Lease 186 granted to mine coal in 4040ha
MPL 156 (71.7ha) granted for shafts, roads, drift and pipelines
MPL 157 (860 ha) granted for buildings, railway and dam.
June 30th 1981, authorisation was received to amalgamate ML186, MPL156 and MPL157 and registered as Bargo Colliery holding.
Proposed Colliery Development:
Coal, men, materials and equipment via a drift – side by side configuration of conveyor belt and track from the surface to the No1 Wongawilli seam bin.
Slope distance of 1595 m at a grade of 1 in 3.5. A 750kW winch haulage with remote operation from the dolly car. Track gge of 1.07m.
Return airway via “clean” shaft – 6.1m diameter, concrete lined, 444 m deep.
Intake airway via a shaft (also 2nd Means of Egress) – 6.1m diameter, concrete lined and some 395m to the floor of the Wongawilli seam.
The intention was to mine the Bulli seam by longwall methods as conditions were similar to the Kemira mine area albeit some 50 m shallower at Bargo.
Coal production was planned at some 2,354,000 t raw coal per annum (Bulli seam) with production commencing in January 1985 at 74,000 tpy ramping up to full production (2.354m tpy) in 1988.
Accommodation was planned for a workforce of 618 employees.
The upcast shaft was sunk by Allied Constructions Pty Ltd, commencing in May 1979 and was completed in January 1981. Some 740 m of roadways were driven in the Bulli seam and 53 m in the Wongawilli seam. A sump of approximately 50 m below the Wongawilli seam was sunk to allow for the bulk winding of coal in the future.
Extract from a memo to the General Superintendent 27/08/1979 regarding current shaft sinking works:-
The erection of the headframe and commissioning of the bucket and stage winder completed on 24/07/1979.
The sidewalls of the fan drift were poured on 6/07/1979.
Mucking out of the spoil left in the shaft during collar completion. The floor of the shaft is currently at -14m.
Pregrouting to -165m completed on 6/7/1979. 148.8 tonnes of cement injected as grout. Top of the “Chocolate Shales” is at -163m.
Boreholes drilled in a circle of 16m diameter, i.e. at 4.8m from the shaft centre.
Standpipes, 37m x 100mm, were inserted in 115mm dia holes and grouted. The holes were then deepened at 75mm dia.
Testing for hydrofracturing on each hole down to 165m, ie 54 hydrofrac. tests, 8 of which fractured. Pregrout project takes 6 weeks to complete.
Extracts from a letter outlining a phone conversation (2/09/1980) concerning the water problems encountered during shaft sinking;
Pregrout holes on shaft perimeter: - 6 x 50mm diameter holes at 7 m radius from shaft centre. Drilled initially to the water table and standpipes inserted. Each hole was drilled deeper by 10 metre intervals, hydrofractured and grouted. All 6 holes were deepened by the 10 m before the drilling the next stage. Drilled to “Chocolate Shales” at 170m.
Water was first encountered at 8 m depth with flows experienced throughout the Triassic. At the base of the Triassic cumulative flows of the order of 300 l/min.
Mr. Terry Abbott concluded that the pregrouting had no beneficial effect at all. Grouting the shaft walls and floor was attempted with little penetration and proved unsuccessful.
Upon completion the total water inflow was gauged at 410 l/min.
The shaft has a sump to 444m, i.e. 52m below the Wongawilli seam floor. Bulli floor to Wonga floor stated to be 20m.
Underground inspections during March 1981 indicated the Bulli seam to have a 2.1 -2.5m section with an undulating roof. Minor percentages of gas were detected, carbon dioxide (CO2) Illawarra bottom gas (CH4/CO2 mix) and methane (CH4) although limited ventilation must have been a contributing factor. The Wongawilli seam had only some 40 metres of roadway formed, insufficient to establish a realistic assessment. The 2.1m resin anchored bolts were proving inadequate with bed separation, some guttering and heavy roof conditions.
Primarily based on the report “Bargo Colliery Project” – Technical Report, 1982
Austral Coal acquired Tahmoor Colliery in late 1997 and also the Tahmoor North deposits.
The Bargo leasehold was acquired by Austral Coal Ltd for some $A 1.3m in 2000 comprising approximately 100 million tonnes of Bulli seam coal and 275 ha of freehold lands, adding it to its’ adjacent Tahmoor Colliery Holdings to the north.
After feasibility studies it was decided that the Tahmoor North coal leases should be developed in preference to the Bargo leasehold.
In 2005, Centennial Coal Co. Ltd gained an 80% majority shareholding in Austral Coal, dissolving the agreement with Roche Mining and taking over their equipment and development activities from 15th April, 2005.
The Bargo Colliery project currently (2007) remains as a future coal resource for Centennial’s Tahmoor Colliery.
Coal & Allied Operations Pty Ltd
Coal & Allied Industries Pty Ltd
A. & A. Brown & Abermain Seaham Collieries Limited
Newcastle Wallsend Coal Co. Pty Ltd
Broken Hill Pty Ltd
Dampier Mining Co.
Centennial Coal Co
Austral Coal Ltd
Allied Constructions Pty Ltd